The changes in fatty acid compositions of microencapsulated egg powder during storage

Egg powders are widely used in food industry because of their microbiological safety and their reduced volume with respect to shelled or liquid eggs. However, drying process itself leads to many changes in egg components, resulting in different functional, physical and chemical properties of eggs after reconstitution. For this reason this study was aimed to be protected against oxidation and degradation of functional properties of egg powder by microencapsulation techniques with suitable wall materials by spray drying method.Functional properties (gelling ability, water holding capacity of gel (WHC), foaming, colour), soluble protein content, peroxide value and fatty acid composition of microencapsulated egg powder by spray drying, were investigated during six months of storage at 20 °C and 50 % RH. For the microencapsulation process, gelatine, lactose, pullulan and their mixtures at equal amounts were used as protein and carbohydrate based wall materials, at a ratio of 10 % (w/w) of the total dry matter.The storage and type of the wall material affected the functional and chemical properties of egg powder. Egg powder encapsulated with lactose showed a reduced value of foaming stability values, on the other hand it was the most stable with respect to colour change and prevention of oxidation, during storage. Adding pullulan as wall material gave rise to high expansion and permanent foam, however gelling properties (gel firmness and WHC) showed the lowest values.Gelatine as wall material also gave rise to increase in foaming properties and provided high WHC and texture values. In addition to this, microencapsulated egg powder especially produced with carbonhydrate based coating material (lactose and pullulan), show more protective effect on polyunsaturated fatty acids (PUFA) against the high temperature and pressure while spray-drying process, compare with bare egg powders (YY and HY).